Oklahoma's Longest Bridge: Lake Texoma Bridges

Spanning the Red River

The Lake Texoma Bridges on I-35 at the Oklahoma–Texas border hold the title: 2.4 miles (3.9 km) total length.

Structure

• Two conventional spans: Concrete/steel girders on piers.
• One floating pontoon span: 1.4 miles (2.3 km) — world's longest floating bridge when built (1968). Rests on 70+ concrete pontoons anchored to lakebed.

Why a Floating Section?

Lake Texoma (Denison Dam, 1944) flooded the Red River valley. The channel depth (up to 100 ft) and soft sediment made traditional piers prohibitively expensive. The pontoon section adapts to water-level fluctuations (up to 30 ft).

Traffic & Maintenance

• Carries ~40,000 vehicles/day (I-35 major NAFTA corridor).
• Pontoon section: speed limit 45 mph, weight monitoring, periodic anchor cable tensioning.
• Major rehab 2010–2012: deck replacement, anchor upgrade.

Runner-Up

I-40 Canadian River Bridge (near Calvin) — 1.8 mi. But Lake Texoma's floating engineering makes it iconic.